Evaporative emissions (EVAP) systems include vapor canisters that capture fuel vapor (e.g., butane) evaporated from liquid fuel (e.g., gasoline) housed in a fuel tank of a vehicle. The trapped fuel vapor is typically circulated into an air box and provided as part of an air/fuel charge that is combusted by an engine. Because the fuel vapor is highly combustible, its use during engine combustion increases engine power/efficiency. In some cases, normal refueling events and diurnal or daily hot soaks of the EVAP system, however, are not enough to evaporate and thereby capture a desired amount of fuel vapor. Accordingly, while such EVAP systems work well for their intended purpose, there remains a need for improvement in the relevant art.